The Force is an energy field in all living things. It separates us, penetrates us and binds us together. If energy can neither be created or destroyed but merely transferred, why would one think it can be "awakened" or gone to sleep?? C'mon JJ, don't let us down!
Well if I can put on my "nerd glasses" for a second I think I have a theory on that. I mean assuming that Clone Wars cartoon show is still "canon" and hasn't been relegated to the "legends" category (like the expanded universe books/etc. And yes, I watched the whole clone wars series. Nerd.). Clone Wars (the one with 22 minute episodes, got canceled with some open story arcs) had some episodes about the dark side taking over, but out of the this imbalance in the yin/yang relationship resulting in a new generation of force wielders would come about (foreshadowing Luke in other words). There were some really strange episodes in that series. Hard to believe it was for kids.
Anyway I think it ties in with that sort of thing. After all, as the story goes the Jedi were effectively extinct by episode 4. The one admiral (whatever) on the death star called it a some old religion and Luke/Han had never even heard of it. So in the sense that the "chosen one" of Luke Skywalker will be rebooting the entire concept of the Jedi order from scratch and it will go from Vader and the emperor being the primary people left doing anything force-related to Luke's new concepts/re-founding of the light side...I'd say it's actually an intriguing/accurate title. Seems like it's a better title than "the light awakens". That doesn't any more sense than "the force awakens"
Of course, if you want to read too much into it you could say this move is really passing the baton on to a new cast of characters. I mean how much running around/falling/jumping/whatever that original cast do, anyway? I would have expected them to be in this movie about as much as Obi Wan was in episode 4. If you look at it that way it could mean it's "30 years later" (as in, decades after Return of the Jedi) and a generation of new light-side Jedi are taking over. So the force is "awake" in that sense. Lots of new Jedi, lots of new people using the force. I haven't read anything about the new movie, I have no idea if this is remotely accurate.